Search

We conceptualized and numerically investigated a photonic crystal fiber (PCF)-based surface plasmon resonance (SPR) sensor for rapid detection and quantification of novel coronavirus. The plasmonic gold-based optical sensor permits three different ways to quantify the virus concentrations inside patient’s body based on different ligand-analyte conjugate pairs. This photonic biosensor demonstrates viable detections of SARS-CoV-2 spike receptor-binding-domain (RBD), mutated viral single-stranded ribonucleic acid (RNA) and human monoclonal antibody immunoglobulin G (IgG). A marquise-shaped core is introduced to facilitate efficient light-tailoring. Analytes are dissolved in sterile phosphate buffered saline (PBS) and surfaced on the plasmonic metal layer for realizing detection. The 1-pyrene butyric acid n-hydroxy-succinimide ester is numerically used to immobilize the analytes on the sensing interface. Using the finite element method (FEM), the proposed sensor is studied critically and optimized for the refractive index (RI) range from 1.3348-1.3576, since the target analytes RIs fluctuate within this range depending on the severity of the viral infection. The polarization-dependent sensor exhibits dominant sensing attributes for x-polarized mode, where it shows the average wavelength sensitivities of 2,009 nm/RIU, 2,745 nm/RIU and 1,984 nm/RIU for analytes: spike RBD, extracted coronavirus RNA and antibody IgG, respectively. The corresponding median amplitude sensitivities are 135 RIU-1, 196 RIU-1 and 140 RIU-1, respectively. The maximum sensor resolution and figure of merit are found 2.53 × 10−5 RIU and 101 RIU-1, respectively for viral RNA detection. Also, a significant limit of detection (LOD) of 6.42 × 10−9 RIU2/nm is obtained. Considering modern bioassays, the proposed compact photonic sensor will be well-suited for rapid point-of-care COVID testing.

Deep wide-flange columns are commonly used in the construction of steel moment-resisting frames (MRFs) to resist lateral seismic loads in high seismic regions in North America. Past studies on deep columns with base plastic hinges located at the first storey of MRFs have indicated that such sections can be prone to significant axial shortening and out-of-plane instability under design-level seismic excitation. Despite significant advancement in the seismic performance of steel wide-flange columns, the effect of limit states observed in the past studies on the member seismic stability response has not been quantified in the framework of the Canadian design practice. Moreover, the influence of three-dimensional response of steel MRFs on the stability of the first-storey columns with base plastic hinging using more representative loading protocols expected under seismic loads, e.g., earthquake accelerations, has not been well comprehended yet. Finally, new supporting data is needed 1) to evaluate the current stability design requirements; and 2) to propose enhanced seismic stability recommendations to improve the design of steel MRFs in Canada. Therefore, this study aims to evaluate the stability response of wide-flange columns of Ductile steel MRFs under seismic loading and propose enhanced stability design recommendations in the framework of the Canadian steel design standard (CSA S16). A prototype five-storey Ductile MRF was selected and designed following the CSA S16 seismic design provisions. Various column design scenarios were considered. The concentrated plasticity-based numerical model of the MRF was then developed, which was used to perform nonlinear response history analyses under the ground motion records representing three predominant seismic actions in western Canada. The global and local responses of the alternative designs were evaluated using nonlinear response history analysis (NLRHA) results. A continuum-based finite element model of the interior and exterior columns isolated from the prototype MRF designs was developed and subjected to the displacements and axial load histories obtained from the NLRHA. The results of the NLRHA of the frame and those from the CFEM of the isolated columns were used to evaluate the CSA S16 stability design requirements. A continuum-based finite element model (CFEM) of an MRF subassembly consisting of the exterior bay plus half of the adjacent interior bay was also created to study the three-dimensional response of steel MRFs. A weak-axis bending moment loading protocol was created using the results of the NLRHA of the MRF subassembly, which in combination with in-plane cyclic displacement history and a constant gravity-induced axial compression load were used to perform a parameter study on column stability response using a refined CFEM representing isolated interior first-storey MRF columns. A total of 52 columns were analyzed by varying the section size, unbraced length, and axial load ratios. The results of this study showed that the equivalent moment factor κ = 0.45 can be used for first-storey columns, which results in a lateral bracing limit of Lb/ry = 70. The CFEM of the MRF subassembly is a good tool to understand the three-dimensional demands of first-storey columns under seismic loading. Moreover, four strength and deformation response parameters, including base moment, axial shortening, out-of-plane displacement, and cross-section twist angle, can be used to determine column instability modes, including out-of-plane buckling at the base and member buckling. Column stability was detrimentally affected by the level of the constant gravity-induced axial load. Finally, a simple, coupled empirical equation as a function of the global slenderness ratio (Lb/ry), cross-section aspect ratio (d/bf), and axial load ratio (Cf/AFy) was proposed to predict the stability response of wide-flange columns with base plastic hinging in the framework of the Canadian steel design standard.

There is a huge development in the Information Technology or IT sector recently. Also, there is a massive use of Geographic Information System or in short, we say as GIS nowadays. Tourism Industry is getting more and more advantage specially from GIS. GIS and Tourism Industry are bonding together in a smooth and progressive manner. In order to connect GIS and Tourism, that means in order to establish a bonding between them network is required or we can say connectivity is required. Network allows nodes to share resources in digital telecommunications. So, GIS and Tourism are interconnected with network. Network form infrastructure of modern society. When tourists visit a new place, they might not know about the place in a detailed manner or it might be just a new place for them. Even services like Google which uses the Navigation system and uses the GIS system might not have all details of a place of very low tourist interests. But here we propose Intelligent Tourist Guide System using Web Development which will help tourists travelling to different parts of the world and also local people can advertise their place in order to make it a Tourist Spot and make their area famous.

Refractive index (RI) is a unique attribute of bio-analytes which highly relies upon their concentrations or the activity/infectivity of the microbes. In this paper, a dual-polarized surface plasmon resonance (SPR) RI sensor based on a decentered propagation-controlled core photonic crystal fiber (PCF) has been studied. Fine-tuned light guidance is realized by scaling down the core air holes. The external surface of the fiber is metalized with a thin gold layer that maximizes the chemical stability by reducing the chances of oxidation. The deposition of the core from the central position reduces the core to analyte distance resulting in efficient coupling as well as greater sensitivity. Finite element method (FEM) based numerical investigation warrants promising sensing performances in wavelength and amplitude interrogation methods. The proposed sensor is viable for the RI range from 1.33 to 1.39, where it demonstrates the highest wavelength sensitivities of 13,700 and 15,400 nm/RIU and highest amplitude sensitivities of 852 RIU-1 and 654 RIU-1 in x-and y-polarized modes, respectively. It also exhibits high sensor resolutions of 7.30 × 10−6 RIU and 6.49 × 10−6 RIU, and high figure of merits of 216 and 256 RIU-1 for x and y-polarized modes, respectively. Along with the liberty of selecting light sources, the highly sensitive nature of the sensor will enable accurate detections of different organic compounds and bio-molecules.

This manuscript develops a framework to deliver prediction of diabetes using the Ensemble-based Machine Learning techniques on Pima Indian Diabetes Dataset (PIDD). We investigate the performance measures of four distinct Machine Learning classifiers separately following by a soft voting classifier in order to enhance the performance metrics of Diabetes Identification. The classifications are estimated according to average classification accuracy, precision, recall, f1 score and ROC AUC of individual classifier models. LightGBM, XGBoost, AdaBoost and Random Forest classifiers are employed as distinct classifiers, and a Soft Voting classifier is further introduced to improve the robustness of performance metrics. Analyzed performance metrics results confirm that LightGBM has produced the optimum result as an individual classifier with accuracy score 94% and ROC AUC 95%, and Soft Voting classifier has additionally improved the complete structure to accuracy score 95% and ROC AUC 96%.

A hexagonal lattice birefringent photonic crystal fiber biosensor based on surface plasmon resonance principle has been offered in this paper. Regarding efficient fabrication aspects, simpler unpolished external sensing style has been selected and implemented for unknown refractive index detection. Numerical analysis of operational variables has been executed using the finite element method (FEM). With silica as the core material, indium tin oxide (ITO) is employed to stage the plasmonic interactions against the analyte. The working window is tuned around telecommunication frequencies. Within this comfortable window, this sensor demonstrates maximum sensitivities of 10000 nm/RIU and 541 $\mathrm{R}\mathrm{I}\mathrm{U}^{-1}$ for dynamic index range 1.33-1.37 in spectral and amplitude interrogations respectively. It has also been addressed that let alone the intrinsic tuning, sensitivity as high as 16900 nm/RIU is achievable in longer wavelength region by sheer thickness modification of ITO.

A photonic crystal fiber (PCF)-based surface plasmon resonance (SPR) sensor is proposed for real-time multi-analyte detection. Semicircular U-shaped slots are excavated inside the PCF to facilitate the excitation of surface plasmon polaritons by reducing the distance between the core and external analyte channels. The evanescent field is controlled via engineered scaled-down air holes. A plasmonic metal layer (gold) is deposited over the U-curved microchannel to enhance the surface plasmons. This asymmetric PCF SPR structure enables superior birefringence controllability, which results in a dominant y -polarized response in comparison to the x -polarized mode. The light-guiding and sensor performance parameters are numerically analyzed using the full vector finite element method. The proposed sensor can detect a wide refractive index (RI) range from 1.33 to 1.43. It demonstrates the maximum wavelength sensitivities of 2000 nm/RIU and 12,800 nm/RIU with sensor resolutions of 5 × 1 0 − 5 R I U and 7.813 × 1 0 − 6 R I U for channels 1 and 2, respectively. The sensor also exhibits a maximum amplitude sensitivity of 1119 R I U − 1 with a high figure of merit of 474 R I U − 1 . The simultaneous dual-analyte detection capability and highly sensitive response with a broad detection range make the proposed sensor distinct and will pave the way for miniaturized medical diagnostics and sensing applications.

This work aims to explain leveled sampling period quantization by monitoring the instantaneous derivatives of the signal. Signal derivatives have been calculated and engaged in sensing signal summits. A differential sharpness or tip detection algorithm consists of one fixed level has been employed here. The detector compares each derivative value with the level to define sampling time into 2 individual time intervals for sharp and soft regions accordingly, then quantizes those and does 1-bit time encoding. Both signal and time codes are combined finally in a semi-synchronous style. The proposal is compatible with any pulse code modulations. Promising reconstructed signals are obtained by this method, in contrast with reconstructed shape and data compression. This paper also includes simulations and comparative discussions.